Along with iOS 11 gold master, or GM, Apple also released watchOS 4 gold master on Tuesday. The update is currently available only to developers and the official public release is coming on September 19th.
“Gold master” refers to to final shipping version of the operating system. There won’t be any changes to iOS 11 between now and next week’s public release.
watchOS 4 sports several new watch faces, including a new Siri face that learns what data you want to see, improved activity tracking, new workouts, all day heart rate monitoring with alerts, music streaming, and more.
watchOS 4 works on all Apple Watch models and will be a free download on September 19th for everyone. Until then, only developers can install and use the new version.